Generally, moisture condensed in a stack enclosure (protective case) causes a decrease of insulation, corrosion of a metal part, and damage to plastic components in a stack of about 400V and a fuel cell system which are disposed in the stack enclosure.
To remove moisture, a ventilation system, in which outer air is injected through a blower or inner air is exhausted using a predetermined negative pressure using a flow of outer air, or a separate dehumidifier (or dehumidifying unit) may be provided.
Furthermore, moisture condensed in the stack enclosure may be removed using a cooling pipe formed at a sidewall or bottom surface of the stack enclosure, in conjunction with a coolant driving device such as a pump.
Since such a system may need to drive a blower for ventilating humid air in the stack enclosure and may use an air circulating and cooling system in which humid air is dehydrated through a separate dehumidifier and heat exchanger and the dehydrated air is injected again, or may be mounted with a pump and a radiation module for circulating coolant to a coolant path formed in the enclosure, the system for dehumidification may consume significant power. As such, dehumidification efficiency may be low.
Accordingly, during operation of the fuel cell or when the fuel cell system is turned off, battery power is continuously consumed, such that there are disadvantages in a decrease of efficiency of the fuel cell system and instability of the fuel cell system at restarting.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.